Japanese Patent Laid-Open No. Hei 8-210487 discloses a technique wherein different shift maps are provided for one range and are selectively used in response to a running state. For example, a technique is disclosed wherein, where a shift lever is fixed to the “1” range, the gradient during running is decided, and on a downhill, a downhill map is automatically selected to permit shift down, but on an uphill or a flat other than a downhill, an uphill map or a flat road map is automatically selected to permit shift up without the necessity for operating the shift lever to the “D” range.
The known technique is specialized to a case of shift at the “1” range and the “2” range and is particularly effective where the vehicle runs on a road along which an uphill and a downhill repetitively appear. However, in such a case that the vehicle continuously runs in the “1” range or the “2” range or in a like case, the known technique is not very advantageous if the fuel cost, engine noise and so forth are taken into consideration. Further, since a sensor for detecting the gradient is required, the cost increases.